Linux: add a switch to support user data migration under singleton lock.

This will be used to support migration to SxS (side-by-side) profiles
on Linux.

BUG=38598
R=thestig@chromium.org

Review URL: https://codereview.chromium.org/23531025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@222446 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 91 insertions, 2 deletions

diff --git a/chrome/browser/chrome_browser_main.cc b/chrome/browser/chrome_browser_main.cc
index 4a04a96..4723a10 100644
--- a/chrome/browser/chrome_browser_main.cc
+++ b/chrome/browser/chrome_browser_main.cc
@@ -146,6 +146,7 @@
 
 #if defined(OS_LINUX) && !defined(OS_CHROMEOS)
 #include "chrome/browser/first_run/upgrade_util_linux.h"
+#include "chrome/browser/sxs_linux.h"
 #endif
 
 #if defined(OS_CHROMEOS)
@@ -1219,6 +1220,11 @@ int ChromeBrowserMainParts::PreMainMessageLoopRunImpl() {
     }
   }
 
+#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
+  if (sxs_linux::ShouldMigrateUserDataDir())
+    return sxs_linux::MigrateUserDataDir();
+#endif  // defined(OS_LINUX) && !defined(OS_CHROMEOS)
+
   first_run::CreateSentinelIfNeeded();
 #endif  // !defined(OS_ANDROID)
 
diff --git a/chrome/browser/sxs_linux.cc b/chrome/browser/sxs_linux.cc
index 4b34260..0d6b7dd 100644
--- a/chrome/browser/sxs_linux.cc
+++ b/chrome/browser/sxs_linux.cc
@@ -6,6 +6,7 @@
 
 #include <vector>
 
+#include "base/command_line.h"
 #include "base/logging.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
@@ -14,12 +15,16 @@
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "chrome/common/chrome_paths.h"
+#include "chrome/common/chrome_result_codes.h"
+#include "chrome/common/chrome_switches.h"
 #include "chrome/common/chrome_version_info.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace {
 
-bool DoAddChannelMarkToUserDataDir(const base::FilePath& user_data_dir) {
+const char kChannelsFileName[] = "Channels";
+
+std::string GetChannelMarkForThisExecutable() {
   std::string product_channel_name;
   chrome::VersionInfo::Channel product_channel(
       chrome::VersionInfo::GetChannel());
@@ -51,7 +56,12 @@ bool DoAddChannelMarkToUserDataDir(const base::FilePath& user_data_dir) {
     // Rely on -Wswitch compiler warning to detect unhandled enum values.
   }
 
-  base::FilePath channels_path(user_data_dir.AppendASCII("Channels"));
+  return product_channel_name;
+}
+
+bool DoAddChannelMarkToUserDataDir(const base::FilePath& user_data_dir) {
+  std::string product_channel_name(GetChannelMarkForThisExecutable());
+  base::FilePath channels_path(user_data_dir.AppendASCII(kChannelsFileName));
   std::vector<std::string> user_data_dir_channels;
 
   // Note: failure to read the channels file is not fatal. It's possible
@@ -94,4 +104,54 @@ void AddChannelMarkToUserDataDir() {
   }
 }
 
+bool ShouldMigrateUserDataDir() {
+  return CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kMigrateDataDirForSxS);
+}
+
+int MigrateUserDataDir() {
+  DCHECK(ShouldMigrateUserDataDir());
+
+  base::FilePath source_path;
+  if (!PathService::Get(chrome::DIR_USER_DATA, &source_path)) {
+    LOG(ERROR) << "Failed to get value of chrome::DIR_USER_DATA";
+    return chrome::RESULT_CODE_SXS_MIGRATION_FAILED;
+  }
+
+  base::FilePath channels_path(source_path.AppendASCII(kChannelsFileName));
+
+  std::string channels_contents;
+  if (!base::ReadFileToString(channels_path, &channels_contents)) {
+    LOG(WARNING) << "Failed to read channels file.";
+    return chrome::RESULT_CODE_SXS_MIGRATION_FAILED;
+  }
+
+  std::vector<std::string> user_data_dir_channels;
+  base::SplitString(channels_contents, '\n', &user_data_dir_channels);
+
+  if (user_data_dir_channels.size() != 1) {
+    LOG(WARNING) << "User data dir migration is only possible when the profile "
+                 << "is only used with a single channel.";
+    return chrome::RESULT_CODE_SXS_MIGRATION_FAILED;
+  }
+
+  if (user_data_dir_channels[0] != GetChannelMarkForThisExecutable()) {
+    LOG(WARNING) << "User data dir migration is only possible when the profile "
+                 << "is used with the same channel.";
+    return chrome::RESULT_CODE_SXS_MIGRATION_FAILED;
+  }
+
+  base::FilePath target_path =
+      CommandLine::ForCurrentProcess()->GetSwitchValuePath(
+          switches::kMigrateDataDirForSxS);
+
+  if (!base::Move(source_path, target_path)) {
+    LOG(ERROR) << "Failed to rename '" << source_path.value()
+               << "' to '" << target_path.value() << "'";
+    return chrome::RESULT_CODE_SXS_MIGRATION_FAILED;
+  }
+
+  return content::RESULT_CODE_NORMAL_EXIT;
+}
+
 }  // namespace sxs_linux
diff --git a/chrome/browser/sxs_linux.h b/chrome/browser/sxs_linux.h
index a6d7b42..cff48f2 100644
--- a/chrome/browser/sxs_linux.h
+++ b/chrome/browser/sxs_linux.h
@@ -19,6 +19,13 @@ namespace sxs_linux {
 // Must be run on FILE thread.
 void AddChannelMarkToUserDataDir();
 
+// Returns true if user data dir migration has been requested.
+bool ShouldMigrateUserDataDir() WARN_UNUSED_RESULT;
+
+// Migrates user data dir to a side-by-side-compatible one.
+// Returns exit code - caller should make the process exit with that code.
+int MigrateUserDataDir() WARN_UNUSED_RESULT;
+
 }  // namespace sxs_linux
 
 #endif  // CHROME_BROWSER_SXS_LINUX_H_
diff --git a/chrome/common/chrome_result_codes.h b/chrome/common/chrome_result_codes.h
index a29de59..5e1106c 100644
--- a/chrome/common/chrome_result_codes.h
+++ b/chrome/common/chrome_result_codes.h
@@ -85,6 +85,10 @@ enum ResultCode {
   // Returned when the user has not yet accepted the EULA.
   RESULT_CODE_EULA_REFUSED,
 
+  // Failed to migrate user data directory for side-by-side package support
+  // (Linux-only).
+  RESULT_CODE_SXS_MIGRATION_FAILED,
+
   // Last return code (keep this last).
   RESULT_CODE_CHROME_LAST_CODE,
 };
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index 9a3947a..30a5657 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -1526,6 +1526,14 @@ const char kPasswordStore[]                 = "password-store";
 #endif
 #endif  // OS_POSIX
 
+#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
+// Triggers migration of user data directory to another directory
+// specified as a parameter. The migration is done under singleton lock,
+// and sanity checks are made to avoid corrupting the profile.
+// The browser exits after migration is complete.
+const char kMigrateDataDirForSxS[]          = "migrate-data-dir-for-sxs";
+#endif  // defined(OS_LINUX) && !defined(OS_CHROMEOS)
+
 #if defined(OS_MACOSX)
 // Forcibly disables Lion-style on newer OSes, to allow developers to test the
 // older, SnowLeopard-style fullscreen.
diff --git a/chrome/common/chrome_switches.h b/chrome/common/chrome_switches.h
index 686240e..6bc8a9f 100644
--- a/chrome/common/chrome_switches.h
+++ b/chrome/common/chrome_switches.h
@@ -426,6 +426,10 @@ extern const char kPasswordStore[];
 #endif
 #endif
 
+#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
+extern const char kMigrateDataDirForSxS[];
+#endif
+
 #if defined(OS_MACOSX)
 extern const char kDisableSystemFullscreenForTesting[];
 extern const char kEnableAppListShim[];